I have data coming in that needs to be viewed as averages by region at the minute level. I have a total line that sums each of the averages, and it works fine for every level of granularity until you get down to the minute. At the minute level, data for some regions comes in before/after others. This makes the total line (really a window sum across region) split into multiple different lines. How can I modify this total line to sum by region as one line (like it does for more aggregated levels of granularity).

The following picture shows what I'm talking about:

Here it is at the hour level of granularity, which works because the end times for each region are the same: